title: Cryoprotective effect of L-carnitine on motility, vitality and DNA oxidation of human spermatozoa.
abstract: Successful cryopreservation for human spermatozoa markedly influences the reproductive outcomes of assisted reproductive technologies. But in spite of its usefulness, cryopreservation significantly decreases sperm quality. l-carnitine has been found to improve the quality of spermatozoa in selected cases with male infertility. Here, we examined the efficacy of l-carnitine in improving sperm motility and vitality and reducing sperm DNA oxidation during cryopreservation. Semen samples from infertile patients (n = 22) were collected and analysed. Cryopreservation medium supplemented with l-carnitine was mixed with the semen at a ratio of 1 : 1 (v/v). The final l-carnitine concentration in each cryovial was 0.5 mg ml(-1) per 5 × 10(6) cell ml(-1) . Controls were cryopreserved without addition of l-carnitine. After 24 h of cryopreservation, thawed sperm samples were analysed for motility, vitality and DNA oxidation. Sperm vitality was assessed by the eosin-nigrosin test, while sperm DNA oxidation was measured by flow cytometry. Addition of l-carnitine significantly improved sperm motility and vitality (P < 0.05) compared with the control. The flow cytometry experiment showed no statistical difference (P > 0.05) in the levels of DNA oxidation between samples and controls. In conclusion, l-carnitine improves human sperm motility and vitality, but has no effect on sperm DNA oxidation after cryopreservation.
authors.affiliation: Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, Jordan.
authors.forename: S
authors.initials: S
authors.lastname: Banihani
authors.forename: A
authors.initials: A
authors.lastname: Agarwal
authors.forename: R
authors.initials: R
authors.lastname: Sharma
authors.forename: M
authors.initials: M
authors.lastname: Bayachou
mesh_terms: D002331:Carnitine / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004247:DNA / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007248:Infertility, Male / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D008297:Male; D010084:Oxidation-Reduction; D012662:Semen Preservation / Q000379:methods*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects* / Q000502:physiology
chemical_list: D003451:Cryoprotective Agents; D004247:DNA; D002331:Carnitine
keywords: DNA oxidation; l-carnitine; motility; sperm cryopreservation; vitality